I am fully naxx geared with some OS/Maly/Uldaar pieces, and in Naxx10/25 My gear score is right at 2300 which is top 350 on my server. In a 5 man instance I am at about 2500dps, on 10 mans I am around 2600-4400dps (Average buffs in small raid), I am doing 2900-5000dps (max buffs) for various fights in 25 man raids.

I would focus more on gear than weapons. 2 handers are hard drop items to get, harder in the 25 man raids, as you are rolling against more people for the rare drops.

Also try to keep your Hit Rating capped. 427 I believe is fury DPS cap. I hover around 465.

Also, work your professions for bonus items in JC or Enchant etc...I am an enchanter and I have top enchants on every item as I get a new item. They add up over a long fight.